The word سدس in the Quran

يُوصِيكُمُ ٱللَّهُ فِىٓ أَوْلَٰدِكُمْ لِلذَّكَرِ مِثْلُ حَظِّ ٱلْأُنثَيَيْنِ فَإِن كُنَّ نِسَآءً فَوْقَ ٱثْنَتَيْنِ فَلَهُنَّ ثُلُثَا مَا تَرَكَ وَإِن كَانَتْ وَٰحِدَةً فَلَهَا ٱلنِّصْفُ وَلِأَبَوَيْهِ لِكُلِّ وَٰحِدٍ مِّنْهُمَا ٱلسُّدُسُ مِمَّا تَرَكَ إِن كَانَ لَهُۥ وَلَدٌ فَإِن لَّمْ يَكُن لَّهُۥ وَلَدٌ وَوَرِثَهُۥٓ أَبَوَاهُ فَلِأُمِّهِ ٱلثُّلُثُ فَإِن كَانَ لَهُۥٓ إِخْوَةٌ فَلِأُمِّهِ ٱلسُّدُسُ مِنۢ بَعْدِ وَصِيَّةٍ يُوصِى بِهَآ أَوْ دَيْنٍ ءَابَآؤُكُمْ وَأَبْنَآؤُكُمْ لَا تَدْرُونَ أَيُّهُمْ أَقْرَبُ لَكُمْ نَفْعًا فَرِيضَةً مِّنَ ٱللَّهِ إِنَّ ٱللَّهَ كَانَ عَلِيمًا حَكِيمًا ۝١١

Allāh instructs you concerning your children [i.e., their portions of inheritance]: for the male, what is equal to the share of two females. But if there are [only] daughters, two or more, for them is two thirds of one's estate. And if there is only one, for her is half. And for one's parents, to each one of them is a sixth of his estate if he left children. But if he had no children and the parents [alone] inherit from him, then for his mother is one third. And if he had brothers [and/or sisters], for his mother is a sixth, after any bequest he [may have] made or debt. Your parents or your children - you know not which of them are nearest to you in benefit. [These shares are] an obligation [imposed] by Allāh. Indeed, Allāh is ever Knowing and Wise.

وَلَكُمْ نِصْفُ مَا تَرَكَ أَزْوَٰجُكُمْ إِن لَّمْ يَكُن لَّهُنَّ وَلَدٌ فَإِن كَانَ لَهُنَّ وَلَدٌ فَلَكُمُ ٱلرُّبُعُ مِمَّا تَرَكْنَ مِنۢ بَعْدِ وَصِيَّةٍ يُوصِينَ بِهَآ أَوْ دَيْنٍ وَلَهُنَّ ٱلرُّبُعُ مِمَّا تَرَكْتُمْ إِن لَّمْ يَكُن لَّكُمْ وَلَدٌ فَإِن كَانَ لَكُمْ وَلَدٌ فَلَهُنَّ ٱلثُّمُنُ مِمَّا تَرَكْتُم مِّنۢ بَعْدِ وَصِيَّةٍ تُوصُونَ بِهَآ أَوْ دَيْنٍ وَإِن كَانَ رَجُلٌ يُورَثُ كَلَٰلَةً أَوِ ٱمْرَأَةٌ وَلَهُۥٓ أَخٌ أَوْ أُخْتٌ فَلِكُلِّ وَٰحِدٍ مِّنْهُمَا ٱلسُّدُسُ فَإِن كَانُوٓا۟ أَكْثَرَ مِن ذَٰلِكَ فَهُمْ شُرَكَآءُ فِى ٱلثُّلُثِ مِنۢ بَعْدِ وَصِيَّةٍ يُوصَىٰ بِهَآ أَوْ دَيْنٍ غَيْرَ مُضَآرٍّ وَصِيَّةً مِّنَ ٱللَّهِ وَٱللَّهُ عَلِيمٌ حَلِيمٌ ۝١٢

And for you is half of what your wives leave if they have no child. But if they have a child, for you is one fourth of what they leave, after any bequest they [may have] made or debt. And for them [i.e., the wives] is one fourth if you leave no child. But if you leave a child, then for them is an eighth of what you leave, after any bequest you [may have] made or debt. And if a man or woman leaves neither ascendants nor descendants but has a brother or a sister, then for each one of them is a sixth. But if they are more than two, they share a third, after any bequest which was made or debt, as long as there is no detriment [caused]. [This is] an ordinance from Allāh, and Allāh is Knowing and Forbearing.